drm/stm: dsi: expose DSI PHY internal clock

DSISRC __________
	               __\_
	              |    \
	pll4_p_ck   ->|  1  |____dsi_k
	ck_dsi_phy  ->|  0  |
	              |____/

A DSI clock is missing in the clock framework. Looking at the
clk_summary, it appears that 'ck_dsi_phy' is not implemented. Since the
DSI kernel clock is based on the internal DSI pll. The common clock
driver can not directly expose this 'ck_dsi_phy' clock because it does
not contain any common registers with the DSI. Thus it needs to be done
directly within the DSI phy driver.

Signed-off-by: Raphael Gallais-Pou <raphael.gallais-pou@foss.st.com>
Acked-by: Yannick Fertre <yannick.fertre@foss.st.com>
Tested-by: Yannick Fertre <yannick.fertre@foss.st.com>
Signed-off-by: Philippe Cornu <philippe.cornu@foss.st.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240129104106.43141-4-raphael.gallais-pou@foss.st.com
This commit is contained in:
Raphael Gallais-Pou 2024-01-29 11:41:06 +01:00 committed by Philippe Cornu
parent b0e83c2c85
commit 185f99b614

View File

@ -7,7 +7,9 @@
*/
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/iopoll.h>
#include <linux/kernel.h>
#include <linux/mod_devicetable.h>
#include <linux/module.h>
#include <linux/platform_device.h>
@ -77,9 +79,12 @@ enum dsi_color {
struct dw_mipi_dsi_stm {
void __iomem *base;
struct device *dev;
struct clk *pllref_clk;
struct clk *pclk;
struct clk_hw txbyte_clk;
struct dw_mipi_dsi *dsi;
struct dw_mipi_dsi_plat_data pdata;
u32 hw_version;
int lane_min_kbps;
int lane_max_kbps;
@ -196,29 +201,198 @@ static int dsi_pll_get_params(struct dw_mipi_dsi_stm *dsi,
return 0;
}
static int dw_mipi_dsi_phy_init(void *priv_data)
#define clk_to_dw_mipi_dsi_stm(clk) \
container_of(clk, struct dw_mipi_dsi_stm, txbyte_clk)
static void dw_mipi_dsi_clk_disable(struct clk_hw *clk)
{
struct dw_mipi_dsi_stm *dsi = priv_data;
struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(clk);
DRM_DEBUG_DRIVER("\n");
/* Disable the DSI PLL */
dsi_clear(dsi, DSI_WRPCR, WRPCR_PLLEN);
/* Disable the regulator */
dsi_clear(dsi, DSI_WRPCR, WRPCR_REGEN | WRPCR_BGREN);
}
static int dw_mipi_dsi_clk_enable(struct clk_hw *clk)
{
struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(clk);
u32 val;
int ret;
DRM_DEBUG_DRIVER("\n");
/* Enable the regulator */
dsi_set(dsi, DSI_WRPCR, WRPCR_REGEN | WRPCR_BGREN);
ret = readl_poll_timeout(dsi->base + DSI_WISR, val, val & WISR_RRS,
SLEEP_US, TIMEOUT_US);
ret = readl_poll_timeout_atomic(dsi->base + DSI_WISR, val, val & WISR_RRS,
SLEEP_US, TIMEOUT_US);
if (ret)
DRM_DEBUG_DRIVER("!TIMEOUT! waiting REGU, let's continue\n");
/* Enable the DSI PLL & wait for its lock */
dsi_set(dsi, DSI_WRPCR, WRPCR_PLLEN);
ret = readl_poll_timeout(dsi->base + DSI_WISR, val, val & WISR_PLLLS,
SLEEP_US, TIMEOUT_US);
ret = readl_poll_timeout_atomic(dsi->base + DSI_WISR, val, val & WISR_PLLLS,
SLEEP_US, TIMEOUT_US);
if (ret)
DRM_DEBUG_DRIVER("!TIMEOUT! waiting PLL, let's continue\n");
return 0;
}
static int dw_mipi_dsi_clk_is_enabled(struct clk_hw *hw)
{
struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(hw);
return dsi_read(dsi, DSI_WRPCR) & WRPCR_PLLEN;
}
static unsigned long dw_mipi_dsi_clk_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(hw);
unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
u32 val;
DRM_DEBUG_DRIVER("\n");
pll_in_khz = (unsigned int)(parent_rate / 1000);
val = dsi_read(dsi, DSI_WRPCR);
idf = (val & WRPCR_IDF) >> 11;
if (!idf)
idf = 1;
ndiv = (val & WRPCR_NDIV) >> 2;
odf = int_pow(2, (val & WRPCR_ODF) >> 16);
/* Get the adjusted pll out value */
pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
return (unsigned long)pll_out_khz * 1000;
}
static long dw_mipi_dsi_clk_round_rate(struct clk_hw *hw, unsigned long rate,
unsigned long *parent_rate)
{
struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(hw);
unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
int ret;
DRM_DEBUG_DRIVER("\n");
pll_in_khz = (unsigned int)(*parent_rate / 1000);
/* Compute best pll parameters */
idf = 0;
ndiv = 0;
odf = 0;
ret = dsi_pll_get_params(dsi, pll_in_khz, rate / 1000,
&idf, &ndiv, &odf);
if (ret)
DRM_WARN("Warning dsi_pll_get_params(): bad params\n");
/* Get the adjusted pll out value */
pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
return pll_out_khz * 1000;
}
static int dw_mipi_dsi_clk_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct dw_mipi_dsi_stm *dsi = clk_to_dw_mipi_dsi_stm(hw);
unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
int ret;
u32 val;
DRM_DEBUG_DRIVER("\n");
pll_in_khz = (unsigned int)(parent_rate / 1000);
/* Compute best pll parameters */
idf = 0;
ndiv = 0;
odf = 0;
ret = dsi_pll_get_params(dsi, pll_in_khz, rate / 1000, &idf, &ndiv, &odf);
if (ret)
DRM_WARN("Warning dsi_pll_get_params(): bad params\n");
/* Get the adjusted pll out value */
pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
/* Set the PLL division factors */
dsi_update_bits(dsi, DSI_WRPCR, WRPCR_NDIV | WRPCR_IDF | WRPCR_ODF,
(ndiv << 2) | (idf << 11) | ((ffs(odf) - 1) << 16));
/* Compute uix4 & set the bit period in high-speed mode */
val = 4000000 / pll_out_khz;
dsi_update_bits(dsi, DSI_WPCR0, WPCR0_UIX4, val);
return 0;
}
static void dw_mipi_dsi_clk_unregister(void *data)
{
struct dw_mipi_dsi_stm *dsi = data;
DRM_DEBUG_DRIVER("\n");
of_clk_del_provider(dsi->dev->of_node);
clk_hw_unregister(&dsi->txbyte_clk);
}
static const struct clk_ops dw_mipi_dsi_stm_clk_ops = {
.enable = dw_mipi_dsi_clk_enable,
.disable = dw_mipi_dsi_clk_disable,
.is_enabled = dw_mipi_dsi_clk_is_enabled,
.recalc_rate = dw_mipi_dsi_clk_recalc_rate,
.round_rate = dw_mipi_dsi_clk_round_rate,
.set_rate = dw_mipi_dsi_clk_set_rate,
};
static struct clk_init_data cdata_init = {
.name = "ck_dsi_phy",
.ops = &dw_mipi_dsi_stm_clk_ops,
.parent_names = (const char * []) {"ck_hse"},
.num_parents = 1,
};
static int dw_mipi_dsi_clk_register(struct dw_mipi_dsi_stm *dsi,
struct device *dev)
{
struct device_node *node = dev->of_node;
int ret;
DRM_DEBUG_DRIVER("Registering clk\n");
dsi->txbyte_clk.init = &cdata_init;
ret = clk_hw_register(dev, &dsi->txbyte_clk);
if (ret)
return ret;
ret = of_clk_add_hw_provider(node, of_clk_hw_simple_get,
&dsi->txbyte_clk);
if (ret)
clk_hw_unregister(&dsi->txbyte_clk);
return ret;
}
static int dw_mipi_dsi_phy_init(void *priv_data)
{
struct dw_mipi_dsi_stm *dsi = priv_data;
int ret;
ret = clk_prepare_enable(dsi->txbyte_clk.clk);
return ret;
}
static void dw_mipi_dsi_phy_power_on(void *priv_data)
{
struct dw_mipi_dsi_stm *dsi = priv_data;
@ -235,6 +409,8 @@ static void dw_mipi_dsi_phy_power_off(void *priv_data)
DRM_DEBUG_DRIVER("\n");
clk_disable_unprepare(dsi->txbyte_clk.clk);
/* Disable the DSI wrapper */
dsi_clear(dsi, DSI_WCR, WCR_DSIEN);
}
@ -245,9 +421,8 @@ dw_mipi_dsi_get_lane_mbps(void *priv_data, const struct drm_display_mode *mode,
unsigned int *lane_mbps)
{
struct dw_mipi_dsi_stm *dsi = priv_data;
unsigned int idf, ndiv, odf, pll_in_khz, pll_out_khz;
unsigned int pll_in_khz, pll_out_khz;
int ret, bpp;
u32 val;
pll_in_khz = (unsigned int)(clk_get_rate(dsi->pllref_clk) / 1000);
@ -268,25 +443,10 @@ dw_mipi_dsi_get_lane_mbps(void *priv_data, const struct drm_display_mode *mode,
DRM_WARN("Warning min phy mbps is used\n");
}
/* Compute best pll parameters */
idf = 0;
ndiv = 0;
odf = 0;
ret = dsi_pll_get_params(dsi, pll_in_khz, pll_out_khz,
&idf, &ndiv, &odf);
ret = clk_set_rate((dsi->txbyte_clk.clk), pll_out_khz * 1000);
if (ret)
DRM_WARN("Warning dsi_pll_get_params(): bad params\n");
/* Get the adjusted pll out value */
pll_out_khz = dsi_pll_get_clkout_khz(pll_in_khz, idf, ndiv, odf);
/* Set the PLL division factors */
dsi_update_bits(dsi, DSI_WRPCR, WRPCR_NDIV | WRPCR_IDF | WRPCR_ODF,
(ndiv << 2) | (idf << 11) | ((ffs(odf) - 1) << 16));
/* Compute uix4 & set the bit period in high-speed mode */
val = 4000000 / pll_out_khz;
dsi_update_bits(dsi, DSI_WPCR0, WPCR0_UIX4, val);
DRM_DEBUG_DRIVER("ERROR Could not set rate of %d to %s clk->name",
pll_out_khz, clk_hw_get_name(&dsi->txbyte_clk));
/* Select video mode by resetting DSIM bit */
dsi_clear(dsi, DSI_WCFGR, WCFGR_DSIM);
@ -445,6 +605,7 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct dw_mipi_dsi_stm *dsi;
const struct dw_mipi_dsi_plat_data *pdata = of_device_get_match_data(dev);
int ret;
dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
@ -514,18 +675,41 @@ static int dw_mipi_dsi_stm_probe(struct platform_device *pdev)
dsi->lane_max_kbps *= 2;
}
dw_mipi_dsi_stm_plat_data.base = dsi->base;
dw_mipi_dsi_stm_plat_data.priv_data = dsi;
dsi->pdata = *pdata;
dsi->pdata.base = dsi->base;
dsi->pdata.priv_data = dsi;
dsi->pdata.max_data_lanes = 2;
dsi->pdata.phy_ops = &dw_mipi_dsi_stm_phy_ops;
platform_set_drvdata(pdev, dsi);
dsi->dsi = dw_mipi_dsi_probe(pdev, &dw_mipi_dsi_stm_plat_data);
dsi->dsi = dw_mipi_dsi_probe(pdev, &dsi->pdata);
if (IS_ERR(dsi->dsi)) {
ret = PTR_ERR(dsi->dsi);
dev_err_probe(dev, ret, "Failed to initialize mipi dsi host\n");
goto err_dsi_probe;
}
/*
* We need to wait for the generic bridge to probe before enabling and
* register the internal pixel clock.
*/
ret = clk_prepare_enable(dsi->pclk);
if (ret) {
DRM_ERROR("%s: Failed to enable peripheral clk\n", __func__);
goto err_dsi_probe;
}
ret = dw_mipi_dsi_clk_register(dsi, dev);
if (ret) {
DRM_ERROR("Failed to register DSI pixel clock: %d\n", ret);
clk_disable_unprepare(dsi->pclk);
goto err_dsi_probe;
}
clk_disable_unprepare(dsi->pclk);
return 0;
err_dsi_probe:
@ -542,12 +726,13 @@ static void dw_mipi_dsi_stm_remove(struct platform_device *pdev)
dw_mipi_dsi_remove(dsi->dsi);
clk_disable_unprepare(dsi->pllref_clk);
dw_mipi_dsi_clk_unregister(dsi);
regulator_disable(dsi->vdd_supply);
}
static int dw_mipi_dsi_stm_suspend(struct device *dev)
{
struct dw_mipi_dsi_stm *dsi = dw_mipi_dsi_stm_plat_data.priv_data;
struct dw_mipi_dsi_stm *dsi = dev_get_drvdata(dev);
DRM_DEBUG_DRIVER("\n");
@ -560,7 +745,7 @@ static int dw_mipi_dsi_stm_suspend(struct device *dev)
static int dw_mipi_dsi_stm_resume(struct device *dev)
{
struct dw_mipi_dsi_stm *dsi = dw_mipi_dsi_stm_plat_data.priv_data;
struct dw_mipi_dsi_stm *dsi = dev_get_drvdata(dev);
int ret;
DRM_DEBUG_DRIVER("\n");